Try checking the mixer setting on linux, because the signal REW is measuring is just noise.
I believe that your sound card has only the mono microphone input and in this hardware configuration you cannot perform the calibration.
In fact the calibration provides two input channels, a reference REF IN and the second measurement IN.
To check if the captured signal is actually noise or signal generated use the RTA and Generator function.
With the Generator function you generate 1Khz sinusoidal and with the RTA function it verifies if you actually have a 1Khz signal level.
If you only see noise you will not find any peak at a high level at 1Khz frequency.
A bit unclear, but I think you're proposing that perhaps the input REW is reading is not actually hearing REW's generated tones? That's not the case, I check with Preferences/Check Levels, or with Measurement/Check Levels, to see if REW is actually receiving audio from the speakers.
I don't have a Linux test environment, just Windows and macOS - too many flavours of Linux. If you have mono sources best unchecking the "Force stereo" option in the soundcard preferences.
The beta 15 comment is new, previously you said 5.19 worked. Have you tried previous 5.20 beta versions and found beta 15 to be the latest that works on your system?
When I first started with REW a few months ago, beta 15 was the latest available. That did seem to work with the Latitude 3150 under Linux, and later versions do not. 5.19 seems to work also. But I would have to go back and and regression test to find out what the
latest working version of REW is there.
It might be useful to try REW on linux, if you want to limit on the different versions, you could test it right on the
Raspberry platform which in fact almost exclusively uses Raspbian derived directly from Debian.
You would also have the advantage of a very cheap hardware platform and a vast community of software and hardware developers.
Think about it John, my advice is definitely interested but it could be useful to have many others using Linux.
Anyway thanks again for all the support and for creating REW.
I think you're speaking to John, but in fact I do have a couple of RPis, I haven't tried them with REW though. What are you using for a microphone/ADC there? And what version of REW?
But today, I discovered that some issue with the front-panel HDMI input on my receiver is causing compatibility problems. After swapping the HDMI cable to a rear input, Windows 10 (1903) on the Latitude 3150 now works and supports 5.1 audio. So I installed REW 5.20 beta24 there.
I have the choice of Java drivers, or ASIO. I'm not sure where ASIO is coming from since I haven't installed ASIO4ALL or any other ASIO driver, my best guess is that it's bundled with the Realtek HD Audio drivers on this machine. ASIO doesn't offer >2 channels on HDMI, and the ASIO control panel is a very simple thing that only sets ASIO sample buffer size.
Sometimes I can get REW to send and receive audio. More often REW can't start the ASIO input, or doesn't receive useful input, and once or twice it has just exited, I forget whether that was from the Preferences dialog or the Measurement dialog.
The configuration that seems to work the best is Java drivers, specifying output device/output on the Denon receiver via HDMI, and input device/input as the Realtek HD ADC and builtin mics. I've "calibrated" that mic to a somewhat random level just to ensure that lack of calibration is not an issue. A Prefs screenshot is below. Attempting to do a measurement shows the same behavior I've described before on Linux, and a familiar looking stacktrace:
Code:
Sep 21, 2019 11:06:53 PM roomeqwizard.RoomEQ_Wizard main
INFO: REW V5.20 Beta 24 running JRE 1.8.0_202 64-bit on Windows 10, en, windows-1252
Sep 21, 2019 11:07:03 PM com.synthbot.jasiohost.AsioDriver <clinit>
INFO: Loaded jasiohost64.dll
Exception in thread "Thread-13" java.lang.NullPointerException
at roomeqwizard.QD.C(y:1060)
at roomeqwizard.QD.run(y:948)
So I think this issue is not Linux specific, but is instead something about the way I'm using REW. Remember, I don't have a UMIK-1 or any measurement-grade USB mic adapter. I've got an IMM-6 and TRRS extension cable, connected to a laptop's headset jack. For an initial REW smoke test I don't even hook up the external mic, I just use the laptop's internal mic. The laptop is connected via HDMI to a Denon AVR-S740H receiver with a 5.1.2 speaker setup. I don't usually bother to calibrate the mic input level, since I don't have a good reference to check against and have not been too interested in level-dependent measurements (I live in an apartment and so my subwoofer's output limits aren't actually interesting or important). If there's other info that'd be helpful in chasing this down, let me know.